To understand the MIRO and ZRS better and confirm the domain formation of current distribution on 2DEG under microwave radiation, a good way is to image the current distribution directly. To accomplish this job, we will measure the magnetic field produced by the current distribution and rebuild the current distribution from this magnetic field profile.
To rebuild the current distribution from the magnetic field profile doesn’t have unique solution in 3D case. However, if the current is restricted to 2D, the problem can be solved uniquely. B. J. Roth et al [J. Appl. Phys. 65, 361 (1988)] developed a mathematical algorithm based on the Fourier transform technique to obtain the 2D current distribution from measured perpendicular component of the magnetic field.
To measure the perpendicular component of the magnetic field, we will use the Scanning Hall Probe Microscope (SHPM). The basic principle of SHPM is the STM technique, but instead of using tunneling tips, SHPM uses a small Hall bar as a scanning probe. When magnetic field acts on the Hall probe, a Hall voltage will be produced by the magnetic field. According to the classical Hall effect, this Hall voltage is proportional to magnetic field perpendicular to the Hall probe surface. Hence, by measuring this Hall voltage, the SHPM can image the profile of the perpendicular component of the magnetic field. For more details of SHPM, please check the website:

http://www.nanomagnetics-inst.com

Dr. Rui-Rui Du
rrd@rice.edu
Rice University Physics & Astronomy
Dell Butcher Hall Rm. 170
1900 Rice Blvd. Ent. 20
Houston, TX 77005

>Office Phone: 1-713-348-5780

>Lab Phone/Fax: 1-713-348-5719